Dannenbaum: Why Have We Criminalized Aggressive War?

Uniquely in international criminal law, the criminalization of aggression is rooted in a wrong inflicted by a state on another state, rather than in a wrong (or collection of wrongs) inflicted on individual human beings by other human beings (whether or not the latter are state agents). Other international crimes, like genocide, also involve wrongs against a collective entity. However, the wrong underpinning aggression is special because it occurs exclusively on the macro level. Even the bloodiest aggressive war need not inflict any criminal wrong on individuals. Or so goes the traditional normative account (shared by those who defend the criminalization of aggression and those who object to that criminalization).

I reject that understanding. Not only are individuals wronged gravely in an aggressive war, the wrongfulness of their treatment as individuals is at the very crux of what explains the criminalization of aggression. It is the normative core of the crime.

To be clear, the dominant view is correct that whether a war is criminal is determined on the macro level by whether there is an inter-state breach. But that inter-state breach cannot explain why waging such wars is criminal. The core moral problem with aggressive war is not that it infringes sovereignty, but that it entails killing, maiming, and destroying in a context that does not warrant the infliction of such profound human harms.

There are five reasons that this is the optimal normative account of the crime of aggression. First, the concept of “sovereignty” or “states’ rights” is indeterminate as a normative guide on the issue of aggression. The criminalization of such wars is at least as great a restraint on state sovereignty as it is a protection of it. Second, what distinguishes aggression from any other sovereignty violation is that it involves widespread killing, not that it involves especially egregious violations of territorial integrity or political independence. Other violations that more effectively and dramatically infringe those sovereign rights are not criminalized. Conversely, there is no sovereignty violation that more directly attacks the physical integrity of human beings than does aggressive war. Third, understanding aggression in this way reconciles it to the broader international criminal law project. Fourth, the claimed imperative to incorporate a restrictive jus ad bellum into twentieth century international law was articulated not in terms of sovereignty, but in terms of human suffering. Finally, the jurisprudence and reasoning of the judges and prosecutors at Nuremberg and Tokyo affirmed their understanding that the prohibition of wrongful killing is normatively central to the crime.

The Article concludes by explaining why clarity on this normative substructure is not merely a point of theoretical accuracy, but has significant upshots for the legal framework. First, genuine unilateral humanitarian intervention may be illegal, but it cannot coherently be deemed criminal. Second, so-called “bloodless aggression” is also unlikely to be criminal, unless it involves a massive, immediate, and direct threat to human life. Third, soldiers who participate in criminal wars are not just participants in a mass criminal action. They are also the immediate perpetrators of the constituent wrongs that make sense of the criminality of that action. This has significant implications for their status under international law. Fourth, recognizing that the victims of aggression are individuals (and not just states) sheds light on how we ought to conceive of reparation in this context.